Background: Nosocomial infections account for about one third of deaths in hospitals. Objective: In this study, we aim to determine the factors affecting the incidence of nosocomial infections in the Intensive Care Units (ICUs) to provide more information for helping improve the prevention and treatment of these infections in the hospitals located in Iran. Methods: This is a comparative cross-sectional study conducted in 2017 on 86 patients admitted to the general ICU of Boo Ali Sina Hospital in Qazvin, Iran. We extracted the patients’ demographic and clinical information (e.g. blood and urine culture results) from their medical records. Findings: The prevalence of nosocomial infections were reported 24.3; 38.4% of infections was related to Acinetobacter and 18.6% to Pseudomonas aeruginosa and other microorganisms. The highest antibiotic resistance in patients was to Cefepime (64%) and Ciprofloxacin (60%). Conclusion: The prevalence of nosocomial infections in the general ICU of the study hospital is relatively high with different strains and varied patterns of antibiotic resistance indicating the need for more comprehensive studies and preventive measures in the country.